Lens Technology

Lens Technology

Thanks to the advancement of lens technology, spectacle lenses are no longer a single, one size fits all solution. There are a variety of different lens types that can be used in glasses, giving patients greater flexibility and control over their vision than ever before.

Single Vision Lenses

Also known as monovision lenses, these lenses are designed to correct the wearer’s vision at just one distance, and have a single prescription covering the entire surface of the lens. They are most often recommended for people who are either short-sighted (myopia) or long-sighted (hyperopia) and who need glasses for a specific activity, such as driving or reading.

Varifocal or Progressive Lenses

Varifocal lenses are multifocal spectacle lenses that can correct a patient’s vision at different working distances, ranging from far distance to reading distance. However, rather than designating different areas on the lenses for different distances with visible lines separating them, progressive lenses have a gradual change so that the wearer can smoothly transition from one lens power to another.

Bifocal Lenses

As you may have guessed from the name, bifocal lenses have either two lens powers depending on which type you choose. Bifocal lenses support distance vision in the top half of the lens, and near vision in the lower half. Trifocal lenses support distance vision in the top third of the lens, intermediate vision in the middle segment and near vision in the bottom third. You will see visible lines separating each segment.

Bifocal lenses are recommended for patients who are short or long-sighted, and those who develop presbyopia, which is the natural hardening of the eye lens, that occurs as we get older. Presbyopia makes it harder for the lens of the eye to adapt to focus at different distances. Bifocal lenses won't suit everyone like those with mobility or balance issues or those needs task specific glasses for the computer. 

Multifocal Lenses

Multifocal lenses are the alternative name given to bifocal and progressive lenses.

Occupational/Office/Computer/"Task Specific" Lenses 

Occupational lenses are prescription lenses that are specifically designed to be worn when doing computer work. We often call them task specific lenses as they can also work for those not on a computer like a musician, housewife or artist. This is because they place the optimum lens power for viewing your computer screen or work arms length away exactly where you need it – which is closer than intermediate vision, but further away than reading material is usually held. Wearing occupational lenses can significantly reduce the negative effects caused by the high visual demands of computeror near work, including blurred vision, redness, dry eyes, double vision and dizziness.

Photochromic Lenses

Also known as photochromic lenses or reactor lenses, these lenses are a special type of lens that transition/darken when in the sunlight and transition/lighten when in softer light or the dark. This versatility gives the wearer the convenience of being able to move between different environments without needing to change their glasses. This makes them extremely cost effective and prevent the wearer from needing to take multiple pairs of glasses out with them. Photochromic lenses also filter out many of the harmful UV rays that are emitted from the sun, helping to keep eyes healthy too. They are ideal for people who spend a lot of time going between inside and outside, or who work outside in varying weather conditions.

Blue Light Lenses

Blue light lenses are specially crafted lenses that contain filters that block out much of the artificial blue light that is produced by digital devices like computers, smartphones and tablets. Natural blue light is actually good for balancing our sleep-wake cycle, boosting our mood and enhancing our cognitive abilities so that we can function better day to day. However, too much blue light, especially from artificial sources, can have the opposite effect. Many people who fail to use blue light lenses can go on to develop digital eye strain, which produces symptoms like eye fatigue, dry eyes, blurred vision, headaches and more. Blue light lenses are recommended for anyone who spends a lot of time working on a digital device.

Polarised Lenses

Polarised lenses are used to reduce eyestrain and improve the quality of vision in patients on especially sunny days, making them ideal for anyone who spends a lot of time outdoors. They can do this because they have a special filter that blocks some of the light from passing through the lens. Vertical light is allowed to pass through, while horizontal light, such as that which bounces off of water and can be blinding, is blocked. Polarised lenses are most often used in sunglasses since they are worn outdoors, and the wearer also needs to protect their eyes from UV damage.

Still have questions about which lens is right for you? Contact us to schedule an eye exam or an appointment to evaluate your individual needs.